Study On Pollution Levels And Of Cleaning Effect Assessment On Central Air Conditioning Ventilation Systems

Objective:to master the characteristic of central air-conditioner and pollution situation firstly.Then select suitable disinfectant and disinfection methods according to the investigation results,And then disinfect central conditioning in Tianjin by using the selected disinfection methods,assessment of the cleaning effect and verification the selected disinfectant and disinfection methods.At last to find practical cleaning and disinfect methods and to guide the corresponding jobs correctly and to guarantee sanitary safety of central air-conditionerMethods:combination stratified sampling with simple random sampling to ensure investigate objections,according to "sanitary standard for central air-conditioner ventilation system",detect 9 indexes,including the dust,etc..Select 4 ordinary disinfectants and study them in laboratory.Then detect the effect of kill bacteria, metal causticity according to "technical standard for disinfection".And then select 5 public places whose central air-conditioner was cleaned and disinfected and detect the selected 9 indexes according to "sanitary evaluation standard for central air-conditioner ventilation system".Results:1.investigation of the pollution status/situation of central air-conditioner in public places in Tianjin.17 hotels in Tianjin was investigated in 2006.Investigations indicate that the pollution status/situation was rather serious of the central air-conditioner ventilation in Tianjin.There were 2 indexes which have low total pass rate:the dust capacity/the accumulated dust mass in inner-wind duct surface(pass rate 27%)and bacterial counts in breeze(pass rate 39.4%).Especially the pass rate of dust in ventilation pipes in 5 star hotel is only 14.3%.Investigation also show that the main reasons of the bad pollution status were as follows:some of the central air-conditioner ventilation system in public places had never been cleaned.2.study of the disinfection technique of central air-conditioner ventilation systemCompare 4 normal/ordinary disinfectants on the effect of kill microorganism, metal causticity and effect of surface disinfection.After consideration of comprehend using,economy,environmental protection,we got conclusions as follows:It is mainly needed to be disinfected on pipes,devices and recycling water.It is best to disinfect pipes,devices by using Dibromo Hain,but best to disinfect recycling water by using chlorine dioxide.3.study of the disinfection effect of central air-conditioner ventilation system5 public places which were cleaned and disinfected was evaluated from 2006 to 2007.the results indicate that the cleaning of wind pipes can decline multiple indexes dramatically including the dust capacity/ the accumulated dust mass,the aerobic bacterial counts and epiphyte counts in dust,the aerobic bacterial counts and epiphyte counts in breezing etc..Conclusion:Most of the central air-conditioner in public places had not been cleaned and disinfected.There were 2 indexes which had low total pass rate:the dust in ventilation pipes(pass rate 27%)and bacterial counts in the breezing(pass rate 39.4%).Especially the pass rate of dust in ventilation pipes in 5 star hotel is only 14.3%.the main reasons of the bad pollution status were as follows:some of the central air-conditioner ventilation system in public places had never been cleaned,it is urgent to improve enforcement the sanitary law.Cleaning and disinfection can greatly reduce the level of the dust,the bacterial counts in dust,epiphyte counts,bacterial counts and epiphyte counts in breezing, guarantee sanitary safety of central air-conditioner.The sanitary issues about central air-conditioner must be publicized much more and make more and more people get to know the importance of central air-conditioner ventilation system pollution,get to know the magnificent effect of cleaning and disinfection.Then prompt the action of cleaning and disinfection.Ultimately protect the health of the whole people.